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When launching FLUENT you receive the following error: Segmentation fault $NO_RUN $EXE_CMD $CX_FLAGS

Resolution 1 : This error is usually a DNS or hosts file issue. Check your /etc/hosts file and verify that your IP Address is correctly mapped to your hostname. Verify that the host name in the /etc/hosts file is the exact hostname in the license.dat file. Also, contact your Systems Administrator and check for DNS issues.

You can try the following:

1.In a Terminal window type: hostname (use the returned hostname in the next command)
2.Type: ping hostname
It should return something as seen in the following example below:

ping hostname.company.com (IP_ADDRESS)

Verify that the IP_ADDRESS that was returned is the correct IP_ADDRESS for your hostname

If it returns the error: "unknown host hostname " open up a Terminal Windows and CD to the /etc directory. Open up the hosts file. The hosts file should contain at least the following:

127.0.0.1 localhost
IP_ADDRESS hostname.company.com hostname

(Where IP_ADDRESS hostname.company.com hostname is the IP ADDRESS on the local machine name and then add the Fully Qualified Domain Name (FQDN))

1.Make the desired updates and save the file.
2.Open up a new Terminal Window and try launching FLUENT again
Verifying the IP Address
You can verify the IP Address by typing:

/sbin/ifconfig -a

and

nslookup hostname.domain.com

Once verified check compare the return value with what is in the /etc/hosts file.

Resolution 2 : Comment out or delete all IPV6 information in the /etc/host file. For example, if you have the following in the /etc/host file put a pound symbol in front of each IBV6 entry and restart the network services.